If You post the data in MKS-values I could do a precise simulation for You.
Anyway on first glance IŽd rather use a smaller front opening and larger back chambers.
The TS-parameters look ok so far, apart from Fs and Qts.
Fs is quite low for such a dipole. Expect the Fb to be ~10Hz lower!
Qts is a bit high for a 15" driver. Experience showed that a Qts above 0.5 is ok with smaller drivers, but with drivers >12" Qts-values around 0.4 and even smaller simply sound more precise, tighter and cleaner.
If the driver is usable will show when it is built in and working, but from the datasheet it is ok so far.

Originally posted by Calvin 1) Anyway on first glance IŽd rather use a smaller front opening and larger back chambers.

2) The TS-parameters look ok so far, apart from Fs and Qts.

3) Fs is quite low for such a dipole. Expect the Fb to be ~10Hz lower!

4) Qts is a bit high for a 15" driver.

5) Experience showed that a Qts above 0.5 is ok with smaller drivers, but with drivers >12" Qts-values around 0.4 and even smaller simply sound more precise, tighter and cleaner.

6) If the driver is usable will show when it is built in and working, but from the datasheet it is ok so far.

jauu
Calvin

1) The front and rear chambers I believe are supposed to match the surface area of the driver used for proper loading for Ripole use.

2) Actually, the PPA15's T/S parameters are near perfect for dipole/ripole use.

3) You WANT the Fs to be low or you will need loads of EQ and power and Xmax to compensate for the low end.

4) Again, for dipole/ripole use, the PPA15's Qts is just about perfect.

5) For a driver operating in a sealed or ported enclosure, this is true. However, for dipole use, these drivers are the most precise, tightest and cleanest I have ever heard. IOW, the PPA15's motor/suspension system has plenty of control over the cone's movement in OB designs.

6) The PPA15 is VERY usable, no doubt about it. Datasheets are worthless and inaccurate when trying to determind the sound of a loudspeaker or subwoofer.

If You post the data in MKS-values I could do a precise simulation for You.
Anyway on first glance IŽd rather use a smaller front opening and larger back chambers.
The TS-parameters look ok so far, apart from Fs and Qts.
Fs is quite low for such a dipole. Expect the Fb to be ~10Hz lower!
Qts is a bit high for a 15" driver. Experience showed that a Qts above 0.5 is ok with smaller drivers, but with drivers >12" Qts-values around 0.4 and even smaller simply sound more precise, tighter and cleaner.
If the driver is usable will show when it is built in and working, but from the datasheet it is ok so far.

jauu
Calvin

Whsat data do you want in MKS system, .. the TS parameters or my ripole dimensions, so far? I'm thinking the TS parameters. Here they are:

This is what I'll have to do to make sure the driver frame fits . Ths top part won't be glued in, but will be held in place by threaded rod .

Calvin, I'll wait on your simulations and build the baffles in the mean time. I thought I followed the rule of thumb correctly ie.
1. opening cross sectional area (rear) = 1/3 x Sd
2. double the front cross sectional area to account for the fact that I'm using 2 drivers per ripole (facing each other).

5) For a driver operating in a sealed or ported enclosure, this is true. However, for dipole use, these drivers are the most precise, tightest and cleanest I have ever heard. IOW, the PPA15's motor/suspension system has plenty of control over the cone's movement in OB designs.

6) The PPA15 is VERY usable, no doubt about it. Datasheets are worthless and inaccurate when trying to determind the sound of a loudspeaker or subwoofer.

Chops, I think what Calvin means is that the ripole construction loads the driver more than a conventional open baffle design and accordingly, the motor has to be able to cope.

We'll find out soon enough. For starters, I'm not going to glue in any of the "spacers" that determine rear or front chamber height, so if the ripole doesn't work out, I'll just make spacers taller to morph the ripole into a conventional w-profile dipole design.

Nothing exciting yet, .. merely cut the panels to size and routed out the magnet pass-through holes. If you can keep the dimensions of the panels to just a little under 16", you should be able to build a pair of cabinets out of one 4 x 8 " sheet of plywood.